Traditional printing devices rely on a mechanically operated carriage to transport a print head in a linear direction as other mechanics advance a print medium in an orthogonal direction. As the print head moves over the print medium an image is formed as ink is deposited on the print medium. This mechanized motion of the print head and print medium may allow for image data to be queued up in a predetermined and predictable manner. The print head will advance over the print medium at a rate that will allow all of the necessary ink to be deposited at each location. Once the print head has passed over a sufficient amount of the surface of the print medium to print the image in memory, the print job is complete.
While this structured movement of print head and media may work well with traditional printers, the random motion of a handheld printing device prevents a similar reliance on the steady, consistent, and predictable advancement of the print head over the surface of the print medium. The user-supplied motion of the handheld printing device may not provide adequate coverage of the print medium. Furthermore, reliance upon visual inspection of the printed image may be insufficient to determine what has been, or has yet to be, printed. This may occur, for example, when a portion of the printed image has some, but not all, of the ink deposited. This type of inadequate coverage may be difficult to detect visually during the printing process, but may have a significant impact to the perceived image quality of the printed image when viewed after the printing process has been completed.